Although the terms prison and jail are used interchangeably, in most states they mean different things. Prisons are secure facilities operated by a state or federal government entity that house people who have been convicted of a felony criminal offense and are serving a sentence of one year or more. Jails are secure facilities operated by a county or city government that house arrestees who are held pending a plea agreement, trial, or sentencing, or individuals who have been convicted of a misdemeanor criminal offense and are serving a sentence of less than one year. Controlled-environment facilities, such as prisons and jails, usually allow their residents to communicate with family, friends, attorneys, and others outside the facility to allow the residents to maintain personal connections and to facilitate their transition back into society upon release. Most controlled-environment facilities allow some form of telephone calls, in-person visitation, video visitation, etc. for such communication.
The controlled-environment facilities usually prohibit residents from engaging in unauthorized communications with individuals outside of the facility. In most controlled-environment facilities, unauthorized cell phones, smartphones, tablet computing devices, and other mobile communications devices that allow a resident to circumvent the approved facility communication systems are considered contraband. Use of contraband communications devices within a controlled-environment facility may pose a security risk and may allow for continued criminal activity by the residents. Possession of a contraband communications device is considered a violation of facility rules and such devices are confiscated by the facility staff when found.
Controlled-environment facility residents obtain access to contraband devices through many different sources, such as visiting family and friends or even facility staff. Residents use the contraband communications devices to circumvent the facility's communication systems, which would otherwise limit who the resident could call and would usually allow for monitoring and/or recording of resident calls. During their communications, inmates may make incriminating admissions, commit further criminal acts, conspire to commit further criminal acts, or leave a trail of incriminating data. By circumventing the facility communication system, however, it may not be possible to monitor and detect such activities.
Authorities operating the controlled-environment facility often try to identify and block unauthorized use of contraband communications equipment. Existing methods for detecting and/or controlling access to contraband communications equipment include, for example, jamming frequencies used for cell phone communications and use of mobile detection equipment (e.g., “wands”). These methods have drawbacks. For example, jamming communication frequencies is typically illegal in the United States and can disrupt authorized communications, and mobile detection equipment usually does not work when a contraband device is powered off.